3D reduced-FOV MR thermometry with fat suppression using a hybrid method combining a 2DRF pulse, parallel imaging, and UNFOLD
نویسندگان
چکیده
Fig.4: Temperature changes of the hottest voxel in 2D cheese experiments. While the conventional sequence (magenta) underestimated temperatures due to the presence of fat, the present method (green) suppressed fat and reduced imaging time by 8-fold. Green line is the result of temporal average over a sliding window of 8 time frames. Fig.2: Excitation profile in a cheese phantom. The distance between side lobes (fat) and center lobe (water) is a multiple of rFOV size (2.25cm). In rFOV images, aliasing could be removed by paralleling and UNFOLD.
منابع مشابه
Fast temperature measurement using a 2DRF pulse enables both reduced-FOV imaging and fat suppression
Fig.4: Temperature changes of a cheese phantom at the hottest voxel during FUS heating experiments. While measurements using GE fast gradient-echo sequence are echo time-dependent (a), the measurements using 2DRF pulse for fat suppression are very similar (b). With excitation pattern of Fig.2d, both fat suppression and 2D excitation were achieved, resulting in improvement in temporal resolution...
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5*560μs pulse (a) left: fat+water, right: water-only (b) left: water-only, right: signal null; (c) left: signal null, right: fat-only (d) left: fat-only, right: fat+water. Fig.2. (a) full FOV fat-water separation at 3T with a 5*1136μs pulse; (b) rFOV separation (RFOV=2) with a 9*1136μs pulse; (c) full FOV separation with a 5*720μs pulse; (d) spatially variable separations with a 5*560μs pulse. ...
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